Opening arguments and the first witness testimony were heard Wednesday in the trial of Cara Rintala, a Granby, Massachusetts woman accused of murdering her wife, Annamarie Rintala, in March 2010. The trial is notable for being the first murder case between a married same-sex couple in the state.

Prosecution and defense attorneys outlined their cases before a 16 member jury and a packed courtroom at Hampshire Superior Court in Northampton. The jury was seated after long selection process over the past week. State prosecuting attorney Steven Gagne outlined his case first. He emphasized the Rintalas’ turbulent marriage – both women had filed for divorce and restraining orders against each other and were burdened by financial debt. Gagne alleged that Cara Rintala chose to end the marriage in the couple’s basement, not in a courtroom.

“The person who ended their marriage that day is seated right here: Cara Lee Rintala. And she ended that marriage with her own two hands.”

As prosecutor, Gagne must prove to the jury Cara Rintala committed first degree murder “beyond a reasonable doubt.” In his opening argument, defense attorney David Hoose noted that he does not have that burden in the trial.

“I don’t have to prove Cara Rintala didn’t kill Annamarie Rintala. I also don’t have to tell Mr. Gagne all the things that are wrong with his case at this point and I don’t have to.”

Hoose argued the 19 month police investigation that led to Rintala’s arrest gave little concrete evidence to prove Rintala’s guilt. Judge Mary Lou Rup said the trial would last about three weeks.